To Eat or Not to Eat a Donut
By Julia Michalak
A large population of the world considers to have a “sweet tooth.” For these people including me, the thought of a chocolate-glazed cheesecake or milk tea boba drink brings overwhelming excitement. Into a late night of studying, I could be found snacking on faworki, a Polish dessert consisting of fried dough twisted into ribbon and covered in layers and layers of powdered sugar. Faworki, or angel wings as they are known in the United States, are only one of the many desserts that indicated my strong preference for all things sugary and sweet. While psychologists suggest that individuals draw this preference from their childhood experiences, recent genetic studies state instead, we can blame it on our genes.
Focusing on one of these new genetic studies, Danish scientists from the University Hospital of Copenhagen identified small changes in the hepatokine fibroblast growth factor 21 (FGF21) gene to be associated with a greater preference for sweets and increased total sugar intake. These changes are called single nucleotide polymorphisms, or SNPs, which are small changes in the human genome that for example make two siblings look different. Dr. Søberg and associates identified a SNP associated with FGF21, rs838133, which has varying effects in controlling sugar preference. While individuals with CC alleles have low preference for sweets or sweet tooth tendency with CT alleles, there is clear evidence for a sweet tooth with the TT alleles (Reference-SNPedia, https://www.snpedia.com/index.php/Rs838133).
Furthermore, in clinical trials part of Søberg’s study, high FGF21 levels and sugar consumption correlated with increased alcohol intake and smoking. In other terms, an individual's extreme preference for sweets may be similar to the experience of people struggling with addiction. While the “need” to snack on gummy worms doesn’t equal the challenge faced by a person addicted to nicotine or any other substance, it is still significant that an individual’s genetic disposition for a sweet taste palate may follow along the lines of an addiction to sugar.
However, the fun connotation that comes along with the term “sweet tooth” isn’t as sweet as what the reality of health concerns is. According to Dr. Bovi from the University of Salerno in Italy, a diet rich in fructose and sucrose is directly linked to obesity. Specifically, the added sugars supply food energy but no other nutrients, provide no satiety which increases food consumption, and in early childhood, fructose is linked to high blood pressure and insulin resistance.
Although some people including myself will use these genetic studies as an excuse to eat the extra slice of apple pie, there is a stronger case that our overall health and well-being lies in our own choices and actions. Nevertheless, it is important to state that one donut won’t hurt anyone, in moderation of course!